End cutter head

ABSTRACT

An end cutter head, e.g. for gear cutting machines, comprising bar tool bits two of which are located together in a common tool receiving slot of the cutter head, and a spacing shim interposed in the cutting direction between the said two bar tool bits.

United States Patent 1 [111 3,760,476 Kotthaus I Sept. 25, 1973 ENDCUTTER HEAD [75] Inventor: Erich Kotthaus, Kloten, SwitzerlandReferences Cited [73] Assignee: Wefkzeugmaschinenfabrik v UNITED STATESPATENTS Oberlikon-Buhrle A G, Zurich, l,650,290 11/1927 Metzger 29/105.]

Switzerland [22] Filed; 8, 1972 Primary Examiner-Andrew R. JuhaszAssistant Examiner-William R. Briggs [21] Appl. No.: 224,486

[5 ABSTRACT [30] Forelgn Apphcanon Priority Data An end cutter head,e.g. for gear cutting machines,

Feb. 12, 1971 Switzerland 2135/71 comprising bar tool bits two of whichare located together in a common tool receiving slot of the cutter U.S.A h d and a pacing interposed in the cutting [51] Int. Cl. 826d ctionbetween the said two bar 1100] bits.

[58] Fieldof Search 29/103 C, 105 R,

r 9 5 1 Claim, 3 Drawing Figures END CUTTER HEAD BACKGROUND OF THEINVENTION The present invention relates to an end cutter head, e.g. forgear cutting machines, fitted with bar tool bits of which two each aretogether located in a common slot in the cutter head.

A bar tool bit is understood to be a bit in which the side faces and topface together with the cutting face form the cutting edge, and in whichthe cutting edge shifts in the shank axis when the faces are reground.There has previously been proposed an end cutter head in which receivingslots inclined to the cutter headaxis and extending in tangential planeseach contain directly contacting tool bits. This known arrangement hasthe advantage that a relatively large number of bits can be accommodatedon a cutter head of given diameter and its cutting performance thusraised. However, it has been found that in this prior art end cutterhead the peeling chip which runs over the cutting face of the nextfollowing bit may become jammed in the tight intervening space betweenthe back of the leading bit and the cutting face of the following bitand thereby prevent the cutter head from working as is desired.

SUMMARY OF THE INVENTION BRIEF DESCRIPTION OF THE DRAWINGS The inventionwill be more particularly hereunder described with reference to anembodiment shown in FIGS. 1 to 3 of the accompanying drawing in which:

FIG. 1 is a plan view of an end cutter head according to the invention,

FIG. 2 is a section taken on II-II in FIG. 1, and

FIG. 3 is a section taken on III-III in FIG. 2.

DETAILED DESCRIPTION OF THE INVENTION Referring to FIGS. 1 to 3 an endcutter head 1 comprises a disc-shaped body 2. This body 2 has a centralbore 4 concentric with the axis 3 of the cutter head for fitting thebody to the driving spindle, not shown, of a gear cutting machine. Thedisc-shaped body 2 is provided around its periphery with slots 5 and 6for the reception of bar tool bits 7, 8 and 9. The slots 5, 6 extend intangential planes of the disc-shaped body 2 and they make an angle withthe axis 3 of the cutter head as will be understood more particularly byreference to FIG. 3. One of the two slots 5 and 6, for instance slot 5,is designed to receive two bits 7 and 8, whereas the other slot 6contains only a single bit 9. The three bar tool bits 7, 8 and 9 form anassociated group of tools for cutting one tooth of a gear, the bits 7, 8and 9 functioning in succession as a roughing tool, an outside-cut tooland an inside-cut tool. The direction of rotation in operation of thecutter head 1 in FIG. I would be anticlockwise.

Interposed between the two tool bits 7 and 8 which share a common slot 5is a spacing shim 10. This shim 10 provides sufficient spacing betweenthe face 11 of the tool bit 8 and the back 12 of the preceding tool bit7. The shim l0 fits into a slot 13 which is centrally symmetrical inrelation to the main receiving slot 5.

The shim 10 is secured to the disc-shaped base 2 by a spot weld 14 andprojects resiliently into the main slot 5. When the bar tool bits 7, 8shift in the direction of their shank axis the shim 10 does notparticipate in this movement.

For securing the bar tool bits 7, 8, 9 in their slots 5 and 6 set screwsI5, 16 are provided. The set screws 15, 16 work in tapped holes l7, 18of a clamping ring 19. The clamping ring 19 is attached to thedisc-shaped base 2, in a manner not shown, so that no rotation betweenthe base 2 and the clamping ring 19 can take place. The axis of the setscrews l5, l6 and hence of the tapped holes l7, 18 are normal to thefaces 20 of the tool shanks. A thrust member 21 is interposed betweenthe screw ends and the bar tool bits and bears against the faces 20 ofthe tool shanks. The thrust member 21 is secured against axialdisplacement in either direction by being located between a flangecollar 22 of the clamping ring 19 and a ring holder 23 attached to theclamping ring 19 in a manner not illustrated.

The above-described end cutter head is merely one embodiment of theinvention. For instance, each group of bits might comprise only twobits, namely an outsidecut and an inside-cut bit mounted as a pair inthe wide slot 5. In such a case the narrower slot 6 would not be needed.

I claim: 1. An end cutter head, e.g. for gear cutting machines, saidhead comprising:

a disc-shaped body having tool receiving slots therein; bar tool blades,two of which are positioned together in one of said tool receiving slotsof said end cutter head; and spacing shims interposed in the cuttingdirection between the said two bar tool blades, said spacing shims beingsecured by a spot weld in a further slot situated symmetrically withrespect to said tool receiving slot and projecting resiliently into saidtool receiving tool receiving slot and projecting resil iently into saidtool receiving slot.

' t '1 i l W

1. An end cutter head, e.g. for gear cutting machines, said headcomprising: a disc-shaped body having tool receiving slots therein; bartool blades, two of which are positioned together in one of said toolreceiving slots of said end cutter head; and spacing shims interposed inthe cutting direction between the said two bar tool blades, said spacingshims being secured by a spot weld in a further slot situatedsymmetrically with respect to said tool receiving slot and projectingresiliently into said tool receiving tool receiving slot and projectingresiliently into said tool receiving slot.